目的：在模拟人体生理条件下，获得7种金属离子介导下，欧前胡素和异欧前胡素与人血白蛋白（HSA）相互作用的荧光猝灭强度、结合位点数、结合常数、作用力类型及对其空间构象的影响。方法采用荧光光谱法和同步荧光光谱法结合，研究金属离子介导下，欧前胡素和异欧前胡素与 HSA 的相互作用。结果金属离子介导下，欧前胡素和异欧前胡素对 HSA 的荧光猝灭增强，同时结合作用增强。作用力主要为氢键和范德华力，不同金属离子介导下其作用力类型不变，但作用力强弱有所改变。对于欧前胡素作用力顺序为：Mg2＋＞ Cu2＋＞ Ni2＋＞ Co2＋＞Zn2＋＞ Fe3＋＞ Al3＋，异欧前胡素作用力顺序为：Cu2＋＞ Zn2＋＞ Fe3＋＞ Co2＋＞ Mg2＋＞ Al3＋＞ Ni2＋。同步荧光光谱结果显示金属离子介导下，欧前胡素和异欧前胡素与 HSA 相互作用后，HSA 的构象均发生改变。结论金属离子的存在促进欧前胡素和异欧前胡素与人血白蛋白相互作用。%Objective To obtain the intensity of fluorescence quenching,binding — site number,binding constant,the influence of reaction type and its effect on the space conformation under simulated human physiological conditions. Methods The interaction of imperatorin and isoimperatorin with human serum albumin(HSA)were investigated using the fluores-cence spectroscopy and synchronous fluorescence spectroscopy in the presence of metal ions. Results Imperatorin and iso-imperatorin enhanced the fluorescence quenching of HSA in the presence of metal ions,as well as conjugation. The hydrogen bond and vander waals force were the major driving force between the imperatorin,imperatorin and HSA. Their strength of force was changed,but the type of driving force unchanged in the presence of different metal ions. For the imperatorin,the order of force strength was Mg2 + > Cu2 + > Ni2 + > Co2 + > Zn2 + > Fe3 + > Al3 + ,for isoimperatorin,the order was Cu2 + >Zn2 + > Fe3 + > Co2 + > Mg2 + > Al3 + > Ni2 + . The results of synchronous fluorescence spectroscopy indicated that the confor-mation of HSA was changed by imperatorin or isoimperatorin in the presence of metal ions. Conclusion The presence of metal ions promoted the imperatorin and isoimperatorin interact with human serum albumin.
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